* {
    box-sizing: border-box;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    overflow: hidden;
}

/* 容器 */
.container {
    padding: 30px;
    max-width: 1000px;
    text-align: center;
    border: solid 3px #000;
    border-radius: 10px;
    /* 018 多云的深圳 */
    background-image: linear-gradient(120deg, #fdfbfb 0%, #ebedee 100%);
}

/* 验证码框 */
.code-container {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 40px 0;
}

/* 验证码 */
.code {
    margin: 1%;
    width: 100px;
    height: 120px;
    font-size: 75px;
    font-weight: 300;
    text-align: center;
    border: solid 1px #eee;
    border-radius: 5px;
    /* 设置插入光标颜色为透明 */
    caret-color: transparent;
    /* 在火狐浏览器中,显示为文本域样式(非标准属性) */
    -moz-appearance: textfield;
}

/* 关键点:此伪元素设置和上一条代码都是为了让input:number的输入框不显示上下箭头!!! */
.code::-webkit-outer-spin-button,
.code::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

.code:valid {
    border-color: lightskyblue;
    box-shadow: 0 10px 10px -5px rgba(0,0,0,.5);
}

.info {
    display: inline-block;
    padding: 10px;
    max-width: 400px;
    line-height: 20px;
    color: #777;
    border-radius: 5px;
    background-color: rgba(255,255,255,.7);
}

@media (max-width:600px) {
    .code-container {
        flex-wrap: wrap;
    }

    .code {
        max-width: 70px;
        height: 80px;
        font-size: 60px;
    }
}